segunda-feira, 26 de dezembro de 2022
√2の肩に無限に√2を乗せたらなぜ2になるのか-Why does it become 2 if √2 is infinitely placed on the shoulder of √2?
quinta-feira, 30 de junho de 2022
The method of coordinates, I. M. Gelfand, E. G. Glagoleva, A. A. Kirilov-EL METODO DE COORDENADAS I. M. Gelfand, E. G. Glagoleva, A. A. Kirilov-Метод координат Гельфанд, Глаголева, Кириллов
Topics school geometry, The method of coordinates, I. M. Gelfand, E. G. Glagoleva, A. A. Kirilov, mathematics Collection opensource This book is about school geometry. According to Professor Israel Gelfand one of the beauties and advantages of mathematics in comparison to other fields of knowledge is that "in order to do mathematics one does not need anything other than a pen or a pencil (well sharpened) and a piece of paper." In memory of Professor ISRAEL GELFAND, a Fund was created at PCRM, called The Israel Gelfand Memorial Fund for Ethical Bio-Medicine.
EL METODO DE COORDENADAS I. M. Gelfand, E. G. Glagoleva, A. A. Kirilov
DOWNLOAD: https://www.academia.edu/61425434/MIR_El_M%C3%A9todo_de_Coordenadas_Gelfand_Glagolieva_Kirillov
DOWNLOAD: https://hi.br1lib.org/book/993997/be39bb
Метод координат
Гельфанд, Глаголева, Кириллов
DOWNLOAD: https://hi.br1lib.org/dl/651799/cc6829
sábado, 4 de junho de 2022
Barton Zwiebach Professor of Physics at the MIT Department of Physics. (ELECTRIC ENGINEERING Universidad Nacional de Ingenieria LIMA PERU)
Barton Zwiebach is presently Professor of Physics at the MIT Department of Physics. Zwiebach was born in Lima, Peru. His undergraduate work was done in Peru, where he obtained a degree in Electrical Engineering from the Universidad Nacional de Ingenieria in 1977.
His graduate work was in Physics, at the California Institute of Technology. Zwiebach obtained his Ph.D. in 1983, working under the supervision of Murray Gell-Mann. He has held postdoctoral positions at the University of California, Berkeley, and at MIT, where he became an Assistant Professor of Physics in 1987, and a permanent member of the faculty in 1994.
Research Interests
Professor Zwiebach¹s specialties are String Theory and Theoretical Particle Physics. His central contributions have been in the area of String Field Theory, where he did the early work on the construction of open string field theory and then developed the field theory of closed strings. Zwiebach has also made important contributions to the subject of D-branes with exceptional symmetry and to the subject of tachyon condensation.
Quantum mechanics as a framework. Defining linearity
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
Quantum mechanics as a framework. Defining linearity
MIT 8.04 Quantum Physics I, Spring 2016
View the complete course: http://ocw.mit.edu/8-04S16
Instructor: Barton Zwiebach
SPEED AND ORBITAL TIME OF THE INTERNATIONAL SPACE STATION (ISS)-Professor, or Engineer Jorge Enrique Llaury Padilla-FACULTY OF ELECTRICAL ENGINEERING-NATIONAL UNIVERSITY OF CENTRO-PERU
sexta-feira, 20 de maio de 2022
Физический факультет В. Г. ЗелевинскMinistry of Education and Science of the Russian Federation Novosibirsk State University Faculty of Physics V. G. Zelevinsky The quantum physics Volume 3 Reactions, relativism. Quantum theory of many bodies.ий Квантовая физика Том 3 Реакции, релятивизм. Квантовая теория многих тел. Квантовый хаос Учебное пособие-
segunda-feira, 7 de fevereiro de 2022
Elementary Mathematics V. V. Zaitsev, V. V. Ryzhkov, M. I. Scanavi-В. В. Зайцев, В. В. Рыжков, М. И. Сканави ЭЛЕМЕНТАРНАЯ МАТЕМАТИКА (RUSSIAN VERSION)-1974
Elementary Mathematics V. V. Zaitsev, V. V. Ryzhkov, M. I. Scanavi
В. В. Зайцев, В. В. Рыжков, М. И. Сканави ЭЛЕМЕНТАРНАЯ МАТЕМАТИКА
The book is a repeated course of elementary mathematics and is designed for those who want to replenish, strengthen and systematize their knowledge. As in the first edition, the content is focused on the programs of entrance examinations to technical universities and, in particular, on the programs of preparatory departments at higher educational institutions, for whose students, we hope, the book will be useful. (The book includes Ch1 - Arithmetic, Algebra and Elementary Functions and Ch2 - Geometry. Each section includes a theoretical part and a large number of problems with solutions.) The first edition of the book was published in 1967, at the beginning of work on the second edition, Mark Ivanovich Scanavi himself died (1972) and the work was continued by his co-authors. In the list of authors of this publication: Zaitsev V.V., Ryzhkov V.V., Scanavi M.I.VI
VIEW FULL TEXT WEB:
domingo, 6 de fevereiro de 2022
Active gate switching control of IGBT to improve efficiency in high power density converters- AUTOR Ghorbani, Hamidreza- Universitat Politècnica de Catalunya. Departament d'Enginyeria Electrònica Document-Doctoral thesis
Active gate switching control of IGBT to improve efficiency in high power density converters
Thesis submitted in partial fulfilment of the requirement for the PhD degree issued by the Universitat Politècnica de Catalunya, in its Electronic Engineering Program
BY Hamidreza Ghorbani
Director: Dr. Prof. Jose Luis Romeral Martinez
Co-Director: Dr. Eng. Vicent Sala -May 2019
Abstract
Insulated gate bipolar transistor (IGBT) power semiconductors are widely employed in industrial applications. This power switch capability in high voltage blocking and high current-carrying has expanded its use in power electronics. However, efficiency improvement and reducing the size of products is one of main tasks of engineers in recent years. In order to achieve high-density power converters, attentions are focused on the use of fast IGBTs. Therefore, for achieving this desire the trend is designing more effective IGBT gate drivers. In gate drive (GD) controlling, the main issue is maintaining transient behavior of the MOS-channel switch in well condition; when it switches fast to reduce losses. It is well known that fast switching has a direct effect on the efficiency improvement; meanwhile, it is the major reason of appearing electromagnetic interference (EMI) problems in switched-mode power converters. Nowadays the most expectant of an active gate driver (AGD) is actively adjusting the switching transient through simple circuit implementation. Usually its performance is compared with the conventional gate driver (CGD) with fixed driving profile. As a result a proposed AGD has the capability of increasing the switching speed while minimizing the switching stress. Different novel active gate drivers (as feed-forward and closed-loop topologies) have been designed and analysed in this study. To improve the exist trade-off between switching losses and EMI problem, all effective factors on this trade-off are evaluated and considered in proposed solutions. Theoretical developments include proposed controlling methods and simulated efficiency of IGBTs switching control. The efficiency improvement has been pursued with considering EMI study in the proposed active gate controller. Experimental tests have been conducted to verify the design and validate the results. Beside technical aspects, cost study has also considered in the closed-loop GD. The proposed gate drivers are simple enough to allow its use in real industrial applications.
RESUMEN
Los semiconductores de potencia (IGBT) se emplean ampliamente en aplicaciones industriales. La capacidad de este interruptor de bloqueo en alta tensión y conducción de alta corriente ha ampliado su uso en la electrónica de potencia. Sin embargo, la mejora de la eficiencia y la reducción del tamaño de los convertidores de potencia es una de las tareas principales de los ingenieros de diseño. Para lograr convertidores de potencia de alta densidad y eficiencia, se requiere el uso de IGBT rápidos. Por lo tanto, la tendencia es diseñar controladores de puerta para IGBT más efectivos. En el control de la unidad de puerta (GD), el problema principal es mantener el comportamiento transitorio del conmutador del canal MOS bajo control, cuando conmuta a lata frecuencia para reducir las pérdidas. Es bien sabido que la conmutación rápida tiene un efecto directo en la mejora de la eficiencia; Sin embargo, la alta frecuencia de conmutación es la razón principal de la aparición de problemas de interferencia electromagnética (EMI) en los convertidores de potencia de modo conmutado. En la actualidad, la acción más directa para un controlador de puerta activo (AGD) consiste en el ajuste activo del transitorio de conmutación a través de la implementación de un circuito simple. Para evaluar su eficiencia, su rendimiento se compara con el controlador de puerta convencional (CGD) con perfil de conducción fijo. Los resultados muestran que la propuesta de AGD tiene la capacidad de aumentar la velocidad de conmutación mientras minimiza el stress. En este estudio se han diseñado y analizado diferentes controladores de puerta activa novedosos (como topologías de control en avance y de bucle cerrado). Para mejorar el balance existente entre la reducción de pérdidas y los problemas de EMI, todos los factores que afectan a las pérdidas y la EMI se evalúan y se consideran en las soluciones propuestas. Los desarrollos teóricos incluyen el análisis y desarrollo de los métodos de control propuestos, la simulación de la operación del control de conmutación del IGBT, y la validación experimental. Además de los aspectos técnicos de eficiencia y emisiones electromagnéticas, el estudio de costes también se ha considerado en los análisis de AGD. Los resultados muestran que los controladores de puerta propuestos son lo suficientemente eficientes y económicos como para permitir su uso en aplicaciones industriales reales [-]
VIEW FULL THESIS:
Assinar:
Postagens (Atom)
